SExtractor及其在深度巡天研究中的应用
The SExtractor and Its Applications in Deep Sky Surveys
查看参考文献12篇
文摘
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SExtractor作为一套从巡天图像中检测天体并提取天体星等、位置等信息的开源软件,已经被广泛运用在深度巡天的目标源提取和测量中。深度巡天中目标源的检测能力(深度)和对轮廓重叠的目标源的分解能力往往比光子噪声带来的测量误差更重要。针对不同研究目的的目标天体的提取往往需要在对目标源的检测能力和分解能力之间进行平衡,在使用SExtractor提取目标源时其参数设定也存在较大差异。介绍了SExtractor在深度巡天中参数的设定,结合分析讨论了SExtractor获取天体目标和测量的精度,同时也发现在深度巡天中使用SExtractor提取目标源存在十分严重的过度分化问题。 |
其他语种文摘
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Deep sky surveys provide fundamental data for studies of formation and evolution of galaxies, galaxy clusters,large-scale structures of the universe,and supermassive black holes. The SExtractor software package is an open-source software system. It can build a catalogue of objects from a sky-survey image and output magnitudes,surface coordinates,sizes,shape descriptions,and other information of objects. The SExtractor has been widely used for detection and measurement of objects in deep sky surveys. For object detection and measurement, abilities to detect objects (for completeness) and to separate objects of superimposed profiles (for resolving confusion) often have a larger impact on results than measurement errors due to photon noise. This requires certain balance between the abilities to detect objects and to separate objects of superimposed profiles. When using the SExtractor,the parameter values should then vary according to different types of objects so as to optimize detection and measurement. To detect apparently small faint objects, low detection thresholds need to be adopted,but low detection thresholds can lead to overdeblending of highredshift galaxies of complex inner structures,or confusion of outer features of bright galaxies /scattered-light features of bright stars to be independent objects. Particularly,overdeblending can cause severe contamination in statistics of high-redshift close pairs identified from deep sky surveys. Confusion from parts of bright galaxies and scattered-light features of stars can be avoided by flexible settings of SExtractor parameter values. Overdeblending of faint galaxies of complex structures remains a difficult problem though. In this paper,we systematically describe the principles and parameters of the SExtractor. By incorporating our own analysis we also discuss accuracies and other measurement problems in using the SExtractor. At last,we give some suggestions to those problems. |
来源
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天文研究与技术
,2016,13(2):266-272 【核心库】
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关键词
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目标检测
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深度巡天
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光度学
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地址
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中国科学院云南天文台, 云南, 昆明, 650011
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语种
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中文 |
文献类型
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研究性论文 |
ISSN
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1672-7673 |
学科
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电子技术、通信技术 |
基金
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中国科学院知识创新工程重要方向项目
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文献收藏号
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CSCD:5686182
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参考文献 共
12
共1页
|
1.
Bertin E. SExtractor: software for source extraction.
Astronomy & Astrophysics Supplement Series,1996,177:393-404
|
CSCD被引
93
次
|
|
|
|
2.
Williams R E. The Hubble Deep Field: observations,data reduction,and galaxy photometry.
The Astronomical Journal,1996,112(4):1335-1752
|
CSCD被引
3
次
|
|
|
|
3.
Yee H K C. A faint-galaxy photometry and image-analysis system.
Publications of the Astronomical Society of the Pacific,1991,103(662):396-411
|
CSCD被引
2
次
|
|
|
|
4.
Stone R C. A comparison of digital centering algorithms.
The Astronomical Journal,1989,97:1227-1237
|
CSCD被引
15
次
|
|
|
|
5.
Kron R G. Photometry of a complete sample of faint galaxies.
The Astrophysical Journal Supplement Series,1980,43:305-325
|
CSCD被引
7
次
|
|
|
|
6.
Graham A W. A concise reference to (projected) Sersic R1 /n quantities,including concentration,profile slopes,petrosian indices,and Kron magnitudes.
Publications of the Astronomical Society of Australia,2005,22(2):118-127
|
CSCD被引
3
次
|
|
|
|
7.
Rix H W. GEMS: galaxy evolution from morphologies and SEDs.
The Astrophysical Journal Supplement Series,2004,152:163-173
|
CSCD被引
5
次
|
|
|
|
8.
Leauthaud A. Weak gravitational lensing with COSMOS: galaxy selection and shape measurements.
The astrophysical Journal Supplement Series,2007,172:219-238
|
CSCD被引
7
次
|
|
|
|
9.
Tasca L A M. The zCOSMOS redshift survey: the role of environment and stellar mass in shaping the rise of the morphology-density relation from z~1.
Astronomy & Astrophysics,2009,503(2):379-398
|
CSCD被引
3
次
|
|
|
|
10.
McCracken H J. The VIRMOS deep imaging survey. II: CFH12K BVRI optical data for the 0226-04 deep field.
Astronomy & Astrophysics,2003,410:17-32
|
CSCD被引
2
次
|
|
|
|
11.
Capak P. The first release COSMOS optical and near-IR data and catalog.
The Astrophysical Journal Supplement Series,2007,172:99-116
|
CSCD被引
7
次
|
|
|
|
12.
Capak P. A deep wide-field,optical,and near-infrared catalog of a large area around the Hubble Deep Field North.
The Astronomical Journal,2004,127:180-198
|
CSCD被引
1
次
|
|
|
|
|